Military Review

Alternative schemes of the helicopter carrier system

50

Mi-17V-5 is the owner of the classic carrier system. Photo by Rosoboronexport


Throughout stories helicopters were regularly offered various designs of the carrier system, but only one of them became classical and subsequently received significant development. Other solutions, providing for different options for the propeller drive, blade designs, functions, etc., could not compete with it. Often, such an outcome of a bold project was due to objective shortcomings and problems.

Technical classics


The classical helicopter scheme provides several fairly simple solutions. In the fuselage of the machine is placed a power plant with a gearbox that delivers torque to the main and tail rotor. The main propeller of large diameter is built on the basis of a swashplate that provides a change in lift and / or maneuvering, and also has several blades of large aspect ratio.

This design is relatively simple, it is well developed and lends itself to easy rebuilding and scaling to meet existing requirements. In addition, it is devoid of some disadvantages, such as the need to seal joints in pipelines or the risk of overlapping blades.


Combat Ka-52. The coaxial scheme, with certain reservations, can be considered a development of the classical one. Photo of the Ministry of Defense of the Russian Federation

However, there are also disadvantages. The helicopter of the classical scheme has limitations on the horizontal flight speed associated with the specifics of the flow around the rotor blades. In some modes, other negative phenomena may occur, such as a vortex ring. With a single main rotor, you have to design a long and strong tail boom to accommodate the tail rotor.

The development of the classical scheme led to the emergence of multi-rotor helicopters with longitudinal, transverse or other placement of several bearing systems. A coaxial scheme has become widespread, in which two screws of a traditional appearance are assembled on a single bushing. Also, the classic support system and a number of its units became the basis for several alternative designs.

Jet propeller


The single-rotor helicopter is faced with the problem of reactive torque, and various solutions have been proposed to deal with it. Back in the thirties, the idea of ​​a rotor with a jet drive appeared almost simultaneously in several countries. Such a propeller is not connected to the engine inside the fuselage and, accordingly, does not force it to rotate in the opposite direction.


An experimental B-7 helicopter at the Monino Museum. An AI-7 turbojet engine is visible on the rear blade. Photo Wikimedia Commons

The jet rotor is distinguished by the presence of its own engines at the tips of the blades. The propeller can be driven by a compact turboprop or ramjet engine. Also known are designs with the supply of compressed gases from a gas turbine engine in the fuselage to the nozzles or to the combustion chamber in the blade.

The jet rotor idea received a lot of attention in the fifties and sixties; a number of pilot projects have been developed in different countries. They were offered as light vehicles of the Dornier Do 32 or B-7 ML type. Mile and Hughes XH-17 heavy transport helicopter. However, none of these samples has progressed beyond small-scale production.


Experienced helicopter Hughes XH-17. The main engines were responsible for supplying air to the combustion chambers at the tip of the blade (foreground). Photo LIFE / oldmachinepress.com

The main problem with the jet propeller is the complexity of the hub. Through it, compressed gas and / or fuel must be supplied to the movable blade, which requires transmission and sealing means. On the blade itself, it is necessary to place an engine of one kind or another, which imposes new requirements on its design. Building a robust design with these capabilities proved to be too difficult, and the expected benefits could not justify the effort.

Crossed blades


In the thirties, a so-called scheme was proposed. synchrocopter. This concept proposes the use of two two-bladed rotors, the hubs of which are placed at a minimum distance with the camber outward. The propellers must rotate towards each other, and the special design of the gearbox excludes the overlap of the blades.


Synchrocopter Fl 265 designed by A. Flettner. Photo Airwar.ru

The synchrocopter carrier system is capable of creating the required lift and providing flight in the same modes as the classical scheme. It has the advantage of being able to increase the overall thrust and lifting capacity, and the expansion of the thrust vectors increases stability in hovering and other modes. In this case, the reactive moments of the two propellers compensate each other and eliminate the need for a steering system.

However, synchrocopters are not widely used. In the thirties, such equipment was produced by the German company Flettner, and since 1945 this topic has been dealt with in other countries. The helicopters of the American company Kaman Aerosystems are best known. Until a certain time, synchrocopters were in demand, but then the direction faded - now there is only one sample in the series. For all the time, no more than 400-500 serial machines of this class were built.


Helicopters Kaman K-Max aviation USMC. Photo Wikimedia Commons

The main disadvantage of a synchrocopter is the complexity of the gearbox, which delivers torque to two closely spaced propellers. A single rotor drive with the same characteristics turns out to be much easier. In addition, a pair of two-bladed propellers have limited thrust potential. So, the modern "heavy" synchrocopter Kaman K-Max lifts no more than 2700 kg and loses in this respect to many helicopters of the classical scheme.

Spin and stop


The idea of ​​combining a rotating propeller and a fixed wing is known. In this case, the rotation of the main rotor is used for takeoff and acceleration. At a certain speed, the propeller must stop, and its blades must turn into a fixed wing. This makes it possible to develop a high flight speed, but requires the development and implementation of new solutions.

As an example, consider the Sikorsky X-Wing project, which has been developed since the mid-seventies to complement the S-72 helicopter. The latter was a helicopter with a main and tail rotor, equipped with a developed wing of a small sweep. On the sides of the fuselage there was a pair of gas turbine engines that provided power to the shaft (for propellers) and created jet thrust (for high-speed flight).


Experienced Sikorsky S-72 helicopter with X-Wing carrier system. Photo by NASA

The X-Wing carrier system received a disc fairing hub equipped with a swashplate with a common pitch only. We used rectangular blades with a vertically symmetrical profile. On the leading and trailing edge of the blade, there were openings for the release of compressed air from the compressor to the outside. The air, due to the Coanda effect, was supposed to "lengthen" the profile of the blade, helping it to create lift. Depending on the way the air is supplied, the blade can work equally efficiently when rotating and in a stationary position.

The X-Wing system was successfully tested in a wind tunnel and was even installed on an experienced S-72. However, shortly before the planned flights, in 1988, NASA and DARPA ordered to stop work. With all the expected benefits, the unusual carrier system was too complex. In addition, the project stretched out for more than 10 years, and its cost exceeded the permissible limit. For this reason, the X-Wing concept was not further developed.

Lens in flight


Right now, the French company Conseil & Technique is working on the concept of a light air taxi helicopter with an unusual carrier system. The proposed design of the propeller loses to the traditional one in terms of the created lift at takeoff and landing modes, but differs in greater simplicity and the ability to create increased thrust in horizontal flight. The ability to reduce noise is also announced.

Alternative schemes of the helicopter carrier system
X-Wing screw operation in different modes. Sikorskyarchives.com

The original propeller is built on the basis of a lenticular disk that occupies 70% of the swept area. It is proposed to mount short blades of the airfoil along its edges. The possibility of placing the swashplate is not reported; traction control can be performed by changing the speed.

Tests have shown that during horizontal flight, the disc part creates a significant lifting force, due to which the structure as a whole bypasses the traditional design propeller in terms of characteristics. In addition, it was possible to bring the angle of attack to 25 ° without stalling the flow. The aircraft under development, according to calculations, will be able to reach speeds of up to 200 km / h.


Concept "air taxi" with lenticular propellers from Conseil & Technique

The Conseil & Technique project is still at the stage of research and design development. Probably, in the near future it will be brought to tests on mock-ups, after which a full-fledged experimental multi-rotor helicopter may appear. It is not known whether this alternative design will be able to solve all the tasks and find a place in the aviation industry.

Looking for alternatives


Long decades of existence and active operation of helicopters have shown all the advantages of the classic design of the carrier system. Attempts to create alternative schemes that have minimal similarity with it have not yet been crowned with special success. However, scientists and engineers do not stop working and continue to search for promising ideas.

Another project of this kind is being created right now, and its results will become clear in the near future. At the same time, it is clear that none of the new bearing systems will be able to have a noticeable effect on the general state of affairs, and the classical scheme and various variants of its development will retain their place in aviation technology. However, new developments - subject to sufficient perfection - can find their niche, where their advantages will be most appropriate and profitable.
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  1. Jacket in stock
    Jacket in stock 30 May 2021 06: 09
    +4
    And it seems to me a promising multi-rotor scheme similar to small drones with a separate electric drive for each small propeller.
    For some reason, the author did not mention such a scheme, although there are already real flying samples.

    There can be several such propellers, some of them, which are smaller, can be rotary to change the thrust vector, non-rotary ones can have a mechanism for changing aerodynamics - just a curtain that covers the propeller section and turns it into a kind of wing.
    This is so, in the order of fantasies, inspired by all sorts of unscientific fantasy films.
    1. Reviews
      Reviews 30 May 2021 06: 35
      +11
      Full size multicopters are "a very big question". For example, small UAVs do not have a transmission that combines the propellers (in case of failure of one of the engines), but for an aircraft weighing several hundred kg, or even several tons, it weighs a lot and takes up a lot of space. And without it in any way - not a light drone, all the same, it's a pity to lose, even if a heavy drone, and not a manned aircraft. Well, and the axiom - N screws weigh more than one screw, and this, when "scaling up", creates problems with the weighting of the structure according to the "rule of squares / cubes".
      1. Jacket in stock
        Jacket in stock 30 May 2021 07: 18
        +4
        Quote: Avis
        small UAVs do not have a transmission that combines the propellers (in case of failure of one of the engines), but for an aircraft weighing several hundred kg, or even several tons, it weighs a lot and takes up a lot of space. And without it in any way - not an easy drone, all the same, it's a pity to lose,

        Funny
        it is in the rejection of the cumbersome, heavy transmission is the essence of the idea.
        And why is the failure of one of 10-12 engines more dangerous than the failure of the only one in the traditional scheme?

        Quote: Avis
        Well, and the axiom - N screws weigh more than one screw, and this, when "scaling up", creates problems with the weighting of the structure according to the "rule of squares / cubes".

        Doesn't it work when scaling a classic transmission?
        It seems to me on the contrary, a heavy gearbox is not just an enlarged small one, it is a fundamentally different design, plus other requirements for materials, etc. and so on. The price is no longer growing in a cube, but twice in a cube. Or maybe not two, but even more.

        Well, the advantage of the multicopter is the absence of any aerodynamic effects associated with the features of large propellers, which again simplifies both design and operation.

        In general, it is necessary to count in each specific case. The mechanic and the electrician are moving forward, and the electrician is much faster, so the issue price is changing rapidly. What was recently fiction is becoming commonplace today.
        1. Reviews
          Reviews 30 May 2021 08: 15
          +7
          Quote: Jacket in stock

          it is in the rejection of the cumbersome, heavy transmission is the essence of the idea.

          It won't work on a large machine. 4-6 rotors, no more.

          And why is the failure of one of 10-12 engines more dangerous than the failure of the only one in the traditional scheme?

          Because on a serious machine (and not any ladies' "air taxis") such a number of engines is stupid. For technical exploitation, vulnerability (not only combat, in the air and just birds fly), logistics of spare parts ... I would have looked at the reaction of tankers who were offered to make a conditional T-114 with a motor-wheel in each track ... Or motorized riflemen with such an armored personnel carrier.
          Doesn't it work when scaling a classic transmission?

          How it works. But I'm talking about something else. A single motor, for example, weighs 2kg and occupies a volume of one brick. Two motors of the same total power, for example, 3kg and two bricks. When increasing
          the overall dimensions are twice the volume of the installations grow in proportion to the squares: up to 4kg and 9kg, respectively. And the weights grow to 1 ^ 3 and 2 ^ 3 (1 and 8) kg.

          Well, plus the multicopter is the absence of any aerodynamic effects associated with the features of large propellers

          On the other hand, there are effects of a set of short-rotating ones. Also, you know, there are some peculiarities.
          1. ycuce234-san
            ycuce234-san 30 May 2021 09: 38
            0
            For technical exploitation, vulnerability (not only combat, in the air and just birds fly), logistics of spare parts ...


            They are all standard and engines and blades and everything else. Just like chips in electronics or parts in radio engineering, logistics is not that much of a problem compared to weight and size difficulties. On the other hand, when flying an electrician, it is better to immediately develop advanced unconventional flying devices - for example, ionic flights. It seems to me that it will be possible for material scientists and electrical engineers to create a mega-insulating material and - semiconductors for ultra-ultrahigh voltages and light generators of high voltages and ionization. The air at the speeds at which the direct-flow engines operate can also be heated in a non-chemical way, for example, by an arc discharge or by electrically heating the surfaces of ceramic heat exchangers in the engine or on the wings. Well, or use microdroplets of water in engines as a consumable - by charging and very strongly accelerating them with an electric field in the engine - they heat up from friction against the air, evaporate and transfer the moment of movement to the air.
          2. Jacket in stock
            Jacket in stock 30 May 2021 09: 42
            -1
            Quote: Avis
            It won't work on a large machine. 4-6 rotors, no more.

            Who said? Where is it counted?
            A single motor, for example, weighs 2kg and occupies a volume of one brick. Two motors of the same total power, for example, 3kg and two bricks. When increasing
            the overall dimensions are twice the volume of the installations grow in proportion to the squares: up to 4kg and 9kg, respectively. And the weights grow to 1 ^ 3 and 2 ^ 3 (1 and 8) kg

            Yes, it is clear.
            But we must count in total, two large engines plus one huge gearbox, or 8 small motors without a gearbox at all. And another question, which will be easier and cheaper. It's even easier to ask questions.
            It is clear that such a scheme has a certain scaling limit, well, so I wrote it - everything changes, the weight / size of the engines decreases, and accordingly the limit is shifted up.

            a duck-sized bird breaks one small rotor, fragments of which damage 2-4 closely spaced propellers and / or motors.
            I can’t even hypothetically imagine, because each propeller-driven group is isolated and separated in distance from the neighboring one.
            But the failure of a single engine, or even one of the two, is a guaranteed fall.
            1. Reviews
              Reviews 30 May 2021 09: 54
              +1
              Quote: Jacket in stock

              Who said?

              History.
              Where is it counted?

              A lot of where. From Dornier X and B-36J to the H-1 launch vehicle and the ETOPS concept.
              However, among helicopters, the situation is the same: the Mi-26 perfectly took over all the functions of the 4-engine 2-rotor V-12. You will, of course, say that at the end of the 1960s there were simply no necessary engines, but this did not mean that two NVs were obligatory and the design bureaus suffered with these NVs; because there are two of them. This is also why the 2-screw "Chinook" / "Sea Night" remained the only representatives of this exotic, and the "Pyasetskie" and Yak-24 became extinct: even two NVs create problems. And> 4-6, even more so.
              I can’t even hypothetically imagine, because each propeller-driven group is isolated and separated in distance from the neighboring one.

              Look, in one of the comments on VOLOCOPTER, look at and evaluate the "isolation diversity".
              accident of a single engine, or even one of two - a guaranteed fall.

              This is not even a guaranteed reduction (for two- / multi-engine aircraft); and for single-engine helicopters there is autorotation, and for 1-engine aircraft there is gliding. Moreover, not a fall. Twin-engine aircraft even take off are required to continue if one of the engines fails, not to mention the continuation of horizontal flight.
              1. Jacket in stock
                Jacket in stock 30 May 2021 10: 11
                0
                Quote: Avis
                History

                This is history that shows that multicopters are easier to make.
                The B-12 is a four-engine because it is stupid not to know how to make one powerful motor. This requires high technologies, which could be mastered much later. But the 2-screw vetolet was also made using simpler technologies.
                Therefore, the Mi-26 also has no competitors to make such a huge propeller, and, most importantly, such a huge gearbox is too difficult.
                With the development of technology, it became possible to make small powerful engines, which in total, even taking into account the "cubes-squares", have become comparable in weight / dimensions with large ones, but much easier and cheaper. And they can make a multicopter the size of the same "lady's" Robinson enthusiasts on the knee. And there it is not far from the size of the Mi-8.
                1. Reviews
                  Reviews 30 May 2021 10: 24
                  +3
                  Quote: Jacket in stock
                  Quote: Avis
                  History

                  This is history that shows that multicopters are easier to make.

                  No, it’s not easier. Show me in history a serial multicopter with an internal combustion engine / gas turbine engine with a carrying capacity of at least 3-4 passengers and a range of at least 500 km. And it’s ridiculous to ask about such an electric car.

                  PRo B-12. I tried to explain the obvious from the very beginning. I did not say anything about the possibility of creating one HB, I talked about the problems inherent in two HBs as a layout.
                  1. Bad_gr
                    Bad_gr 30 May 2021 13: 00
                    0
                    Quote: Avis
                    Show me in history a serial multicopter with an internal combustion engine / gas turbine engine with a carrying capacity of at least 3-4 passengers and a range of at least 500 km.
                    Not a serial one, of course, but it is considered as an option (as an example of a multi-engine design).
                    1. Reviews
                      Reviews 30 May 2021 13: 20
                      -1
                      Quote: Bad_gr
                      Not serial, of course

                      Well, when / if it goes into series, then we'll talk.
      2. garri-lin
        garri-lin 30 May 2021 07: 19
        0
        The multicopter does not need a torque transmission system between the nacelles. In the event of a failure of one engine, the neighboring ones are simply transferred to an enhanced mode of operation. For landing, this should be enough even with a large load on board.
        1. Reviews
          Reviews 30 May 2021 08: 17
          +1
          Quote: garri-lin
          The multicopter does not need a torque transmission system between the nacelles. In the event of a failure of one engine, the neighboring ones are simply transferred to an enhanced mode of operation. For landing, this should be enough even with a large load on board.

          Given: a duck-sized bird breaks one small rotor, the fragments of which damage 2-4 closely spaced propellers and / or a motor.
          Objective: Explain the implications for aircraft balancing.

          angle of attack 90 degrees relative to the axis of rotation

          Hmm ...
          1. garri-lin
            garri-lin 30 May 2021 10: 33
            0
            Well, in the event of a collision with such a fatal duck, the transfer of torque from other nacelles will not help. No way at all. Not to mention the possible harm from the possible imbalance of such shafts from the impact of the same megafatal duck.
            1. Reviews
              Reviews 30 May 2021 10: 45
              0
              Quote: garri-lin
              Well, in the event of a collision with such a fatal duck, the transfer of torque from other nacelles will not help. No way at all. Not to mention the possible harm from the possible imbalance of such shafts from the impact of the same megafatal duck.

              There is nothing "mega-fatal" about it. Design case, one of the certification points. "Megaphatal" is, say, an ostrich. But he doesn't fly.
              Larger rotors will be larger, stronger and farther apart. So it's harder to damage them. And, if one engine from 2/3 / etc is lost, then the hated cross transmission will keep the thrust symmetry.
              1. garri-lin
                garri-lin 30 May 2021 11: 10
                0
                I was talking about multicopters. Not even about quadcopters. 6 or more rotors. Here the dependence on one particular rotor is less. And the most important thing. The cross transmission, as you put it, will only save in case of engine failure. And what could be more reliable than an electric motor? The intermediate gearbox added between the motor and the rotor for connecting the shaft becomes the weakest point in the circuit.
                1. Reviews
                  Reviews 30 May 2021 11: 32
                  0
                  Quote: garri-lin
                  I was talking about multicopters. Not even about quadcopters. 6 or more rotors. Here the dependence on one specific rotor is less.

                  And they are more dependent on each other in case of damage, I repeat again.
                  what could be more reliable than an electric motor?

                  I do not know. I don't know what an "electric motor" is.
                  1. garri-lin
                    garri-lin 30 May 2021 19: 06
                    0
                    Dependency is completely design dependent. The relative spread of the rotors and the power reserve of each particular one. That is why they are following the path of increasing the number of rotors. And they try to place them as equidistant as possible from the center of mass.
                    1. Reviews
                      Reviews 30 May 2021 19: 12
                      -1
                      Quote: garri-lin
                      Dependency is completely design dependent. The relative spread of the rotors and the power reserve of each particular one. That is why they are following the path of increasing the number of rotors. And they try to place them as equidistant as possible from the center of mass.



                      You yourself do not understand what you are writing. As with the "angle of attack 90 ° to the axis of rotation". Go ... to school.
                      1. garri-lin
                        garri-lin 30 May 2021 19: 21
                        0
                        I'm not Russian. I'm forgiven. But you are not ashamed to write nonsense. The example with the duck just begged for criticism. Well, they already explained to you. By the way, what's wrong with the phrase? How should this sound in the language of a literate engineer?
              2. Jacket in stock
                Jacket in stock 30 May 2021 13: 08
                0
                Quote: Avis
                ... And, if one engine from 2/3 / etc is lost, then the hated cross transmission will keep the thrust symmetry.

                Actually, in your task, it is not so much the engine that is destroyed as the rotor. And how the transmission will help him with this is not at all clear.
                Quote: Avis
                Larger rotors will be bigger, stronger and farther apart

                Further from what? If the rotor is one, it just breaks and that's it.
                1. Reviews
                  Reviews 30 May 2021 13: 39
                  +2
                  in your task, it is not so much the engine that is destroyed as the rotor. And how the transmission will help him with this is not at all clear.

                  Yes, I didn’t explicitly remind that I’m talking about full-size multicopters of relatively small rotational speed - 4-6, and not about small UAV-multicopters and all sorts of electric rattles for 1-2 people.
                  And on a 4-6 rotor, it will not be possible to compensate for the failure of one engine by increasing the mode on the remaining ones - it will overturn it. Balancing is broken. And then he showed that the multicopter, beloved by my opponent, has a similar problem, only connected not with the failure of the motor, but with the destruction of the propeller. And, if the engines are becoming more and more reliable every year, then the birds in the sky have not gone anywhere, and the number of aircraft is growing, so the destruction of the propeller is almost more likely a cause than engine failure. And, as you know, the more units of the same type in the system, the more, all other things being equal, the greater the probability of failure in it.
                  So, for an "adult" multicopter with a small number of engines (1-3) and propellers (4-6), cross transmission is required.
                  Further from what?

                  I wrote - from each other.
                  If the rotor is one, it just breaks and that's it.

                  ... then he's just a helicopter and that's it. But we're talking about multicopters. I am "rooting" for 4-6 rotors, the rest - for "8-10 and more".
                  1. Jacket in stock
                    Jacket in stock 30 May 2021 14: 25
                    0
                    Quote: Avis
                    cross transmission is required.

                    They did not answer their own question.
                    Rotor failure is much more likely than engine failure. How will the transmission help with this?
                    You do not.
                    The transmission is more likely to exit than the engine, why the transmission?
                    For no reason, it only worsens all parameters, incl. and reliability.
                    Quote: Avis
                    multicopter with a small number of engines (1-3) and propellers (4-6)

                    A meaningless construction.
                    Each rotor has its own engine and must be electric. Otherwise, an ordinary classic helicopter is better.
                    1. Reviews
                      Reviews 30 May 2021 14: 39
                      +2
                      Quote: Jacket in stock
                      Quote: Avis
                      cross transmission is required.

                      They did not answer their own question.

                      Come on...
                      If the screw is destroyed, the transmission will do nothing.
                      If the transmission fails, it will help or not, the question of its design. In general, it is quite simple.
                      If the motor fails, the transmission will help.
                      This applies to large 4-6 rotors. I did not touch on large multi-rotor boats, because I consider them to be pampering. There, the transmission will not help anything at all - it simply will not take off with such a "string bag" from the shafts.

                      The transmission is more likely to exit than the engine

                      Nope. This is not the main gearbox of the helicopter. It is relatively simple as a bicycle and has less space and is generally hidden inside. Neither the bird will reach nor the bullet will hit (well, unlikely to hit). Just don't make it too wide, i.e., limit the screws to 4-6 pieces.
                      Each rotor has its own engine and must be electric.

                      Show me such a miracle. I repeat: 3-4 passengers, range of at least 500 km. even with the usual engines there is no such thing, and even more so with electric trains.
                      For me, a conservative, a helicopter is better, yes. But, if, all the same, to talk about multicopters, then ... see above.
                    2. niksfromru
                      niksfromru 3 June 2021 15: 55
                      0
                      Why did you decide that transmission or rotor failure is more likely than engine failure? Air travel statistics rather suggest otherwise. A multi-rotor scheme with screws devoid of common and cyclic pitch control has two fundamental disadvantages.
                      1) Control is carried out by changing the speed. This does not allow the engine to operate at the optimal speed and requires a senseless waste of power to change the kinetic energy of the rotor rotation. To increase the efficiency of the main rotor, it is desirable to increase its diameter. But the moment of inertia of the propeller is proportional to the square of the blade length! This barrier cannot be overcome by any engine improvement.
                      2) The impossibility of using the autorotation mode in an emergency. Not only one engine can fail, but the entire battery or gas tank. :)
                      3) As an aircraft modeller with 35 years of experience, I can say that the reliability of an internal combustion engine is higher than that of an electric motor with a power converter.
                      At least, only models with an electric power plant were on fire. ;)
                      There is a range of applications for multi-rotor boats, but rather narrow.
                  2. garri-lin
                    garri-lin 30 May 2021 18: 56
                    0
                    The blades of the helicopter hold the chamber with a large caliber bullet or a small caliber projectile. Plus periodically there is information about aircraft disasters associated with collisions with birds. But I honestly don’t remember the same information about helicopters. So how likely it is statistically to destroy the rotor of a multicopter from a collision with birds.
    2. garri-lin
      garri-lin 30 May 2021 07: 22
      0
      No shutter needed. Frequent blades, which, if the angle of attack is set to 90 degrees relative to the axis of rotation, will close together into a solid disk.
  2. Olezhek
    Olezhek 30 May 2021 06: 12
    -1
    The original propeller is built on the basis of a lenticular disk that occupies 70% of the swept area. It is proposed to mount short blades of the airfoil along its edges.


    I understood everything else - I did not understand this option
    More details would be
    Too original and short
    1. Jacket in stock
      Jacket in stock 30 May 2021 06: 25
      0
      Quote: Olezhek
      I understood everything else - I did not understand this option

      According to the scheme, you really can't understand anything, but the concept picture becomes clearer.
      The short blades provide lift. The disc to which they are attached acts as a wing.
      1. Babay Atasovich
        Babay Atasovich 30 May 2021 07: 00
        +2
        The short blades provide lift. The disc to which they are attached acts as a wing
        back in the early 90s, an engineer from the Tractor Plant in Volgograd was running around patent and design bureaus with a working model of his disc. Then the military noticed him. In the 95th, it seems, in Engels, the strategists were already driving a large model, I saw a disk helicopter with my own eyes laughing ... Only now I understood the principle. Then everything calmed down and flashed in the XNUMXs, when the mayor of Moscow talked about the imminent launch of an air taxi. Well, the identity has sunk. request
        1. Babay Atasovich
          Babay Atasovich 30 May 2021 07: 32
          +3
          Sorry! !!! This was Shchukin's EKIP, not a helicopter at all - I recognized it by its contours laughing
  3. Reviews
    Reviews 30 May 2021 06: 25
    0
    On the sides of the fuselage there was a pair of gas turbine engines that provided power to the shaft (for propellers) and created jet thrust (for high-speed flight).

    Still, there are two pairs of engines, it is clearly visible even in the photograph: two on HB, two on propulsion.
  4. Nikolaevich I
    Nikolaevich I 30 May 2021 06: 26
    +6
    I remembered an anecdote (!): Buratins are going on the bus ... Suddenly the driver brakes sharply ... it is clear what happens in such cases? Pinocchio shouts: Has he become impudent or what? You're not carrying firewood! So I think: for whom does the Author take us? Fir-trees! Where is B-12? Yak-24 with Chinook? Multicopters? Why not mention the "disc-shaped" circuits? "Vertical aircraft" take off and landing on the "tail"? am
    In-12
    Yak-24
    VOLOCOPTER
    "DISK"

    TAKE-OFF-LANDING on the TAIL
  5. Thrifty
    Thrifty 30 May 2021 07: 58
    -2
    What the French "offer" in Soviet times in the 50-70s was described in the popular magazine Technology for Youth, with drawings and explanations of the authors! I will not be surprised if this idea of ​​ours was taken from there, from the magazine by the French! Or, in general, they were cut one to one!
  6. Normal
    Normal 30 May 2021 09: 56
    0
    Each scheme has its own advantages and scope. We have established two schemes.
    Classical, with a "tail" propeller carried out on the beam. (Mi-1,2,4,6,8, 26, XNUMX, XNUMX, XNUMX, XNUMX, etc.) is the most simple, proven, reliable and widespread.
    Coaxial. (Ka-26,32,50, etc.) Smaller propeller diameter, Compactness, possibility of basing in a limited space of the ship's deck No power losses to the tail rotor and, therefore, high carrying capacity per power unit.

    Everything else has not become widespread in our country.

    Over the hill, everything is somewhat more diverse (Chinook and Kaman), but again these schemes are rather exotic and do not make the weather.

    Recently, the main rotor - pushing rotor scheme has been developed. Sikorsky SB-1 Deviant and its analogues
    And also in the light and ultra light segment the gyrocopter is experiencing its second youth.
    1. CastroRuiz
      CastroRuiz 31 May 2021 19: 46
      0
      Will the lamprey also have a push screw?
  7. Normal
    Normal 30 May 2021 10: 15
    +1
    Here are more options

    1. niksfromru
      niksfromru 3 June 2021 16: 06
      0
      This is a unique rotorcraft - the CarterCopter autogyro with a "slowed down" rotor. At cruising speed, lift is created by the wing, and the rotor begins to rotate significantly slower to reduce drag. So to speak, the tiltrotor - without changing the visible appearance.
  8. Monar
    Monar 30 May 2021 12: 47
    +2
    This design is relatively simple, it is well developed and lends itself to easy rebuilding and scaling to meet existing requirements.

    A strange statement. This is like taking the same Mi-1. We recalculate the sizes. And oops. Mi-26?
    The coaxial scheme has become widespread,
    Someone will tell you, but besides the Kamov Design Bureau, who makes them in series?
    1. Undecim
      Undecim 30 May 2021 13: 38
      +1
      Someone will tell you, but besides the Kamov Design Bureau, who makes them in series?

      Currently, no one.
      1. Undecim
        Undecim 30 May 2021 18: 22
        -2
        Interestingly, what was the minus individual trying to refute?
    2. Reviews
      Reviews 30 May 2021 13: 52
      +1
      [quote = Monar]
      A strange statement. This is like taking the same Mi-1. We recalculate the sizes. And oops. Mi-26? [/ Quote]

      A little oversimplified, but, in principle, correct. Of course, such a scaling up by three orders of magnitude "head-on" is impossible from an engineering (design, design) point of view, but, in any case, aerodynamics has already been fully worked out. For example, work on the Mi-8 was started by scaling up the Mi-4. EMNIP, even part of the transmission was retained there. And the first B-8 was single-engine, like the Mi-4. So, the Yuryev-Sikorsky scheme is, indeed, the most worked out and the simplest. No wonder it is "classic". A huge bank of data, experience, statistics ...
      In coaxial and longitudinal / transverse schemes, the mutual influence of the screws will be more complicated. And the coaxial ones also have a bushing with a swash plate, which is still ... a nut. It is, indeed, more difficult to scale.

      [Quote] A coaxial scheme has become widespread, [/ quote] Someone will tell you, but besides the Kamov Design Bureau, who makes them in series?
      [/ Quote]
      No one. Even SB> 1 is "not quite" a coaxial axis ...
      1. Normal
        Normal 30 May 2021 14: 21
        +2
        Quote: Avis
        For example, work on the Mi-8 was started by scaling up the Mi-4. EMNIP, even part of the transmission was retained there.
        That is yes.
        But the Mi-4 has one piston ASh-82V, and the Mi-8 has two turboshaft TV2-117, later TV3-117.

        Quote: Avis
        Even SB> 1 is "not quite" a coaxial axis ...

        Not a coaxial at all.
        1. Reviews
          Reviews 30 May 2021 14: 25
          +1
          [quote = Normal]
          But the Mi-4 has one piston ASh-82V, and the Mi-8 has two turboshaft TV2-117, later TV3-117. [/ Quote]

          I am aware of the Mi-4 and Mi-8. I wrote about stage B-8.


          [quote = Avis] Even SB> 1 is "not quite" a coaxial ... [/ quote]

          Not a coaxial at all. [/ Quote]
          Well, actually, his HB is, after all, coaxial. Not in a helicopter sense.
          1. Normal
            Normal 30 May 2021 19: 23
            0
            Quote: Avis
            His HB is, after all, coaxial.

            Of course.
            Che-that I blunted. belay
            I’m sorry.
  9. The comment was deleted.
  10. Operator
    Operator 30 May 2021 17: 23
    +3
    Cycle is our everything

  11. Aleksandr97
    Aleksandr97 31 May 2021 13: 11
    +1
    The main direction of "improvement" of helicopters is to achieve, conventionally, airplane speeds while maintaining vertical take-off and landing. It is clear that alternative movers are rotors, multi-motors, etc. for all the innovativeness and possible improvements in economy, the increase in horizontal speed will not give. While the options are being worked out around the idea of ​​using additional pushing motors:


  12. Lew
    Lew 3 June 2021 09: 32
    0
    always did not understand why to cross a helicopter and an airplane. They have different tasks. you want to be mobile and ubiquitous, you have a helicopter, you want to be fast and high-speed, you have an airplane ... Well, you cannot be both at the same time with a fan and a jet thrust ...
    1. niksfromru
      niksfromru 3 June 2021 16: 15
      0
      Unfortunately, there is a wide range of tasks that neither classic helicopters nor airplanes can solve. "Mobile and ubiquitous" has insufficient range to deliver cargo to an unequipped site, and "fast and high-speed" are able to fly there, but cannot land.
  13. gridasov
    gridasov 8 June 2021 09: 16
    +1
    The problem is not with the new device for converting air or liquid streams. The problem is in understanding the essence of physical processes in fluid dynamics and the application of new methods for analyzing big data. The propeller or propeller can be replaced by a device operating on the use of such properties of the external environment, which are simply ignored. Absolutely all problems of sustainable flight, takeoff, landing, energy efficiency and economy, multiple increase in payload, etc. are being solved.